The International Space Station (ISS) will be de-orbited and sunk in the Pacific Ocean after 2020 like its Russian predecessor Mir, Russian Space Agency (Roscosmos) Deputy Head Vitaly Davydov said on Wednesday.

"We will be forced to sink the ISS. We cannot leave it in orbit as it is a very complicated and a heavy object. There must be no space waste from it," Davydov said in an interview posted on the Roscosmos website.